Tool for making electrical connections



March 12, 1968 H. E. STINE, JR 3,372,454

TOOL FOR MAKING ELECTRICAL CONNECTIONS Filed Sept. 29, 1965 v 4 Sheets-Sheet 1 March 12, 1968 H. E. STINE, JR

TOOL FOR MAKING ELECTRICAL CONNECTIONS 4- Sheets-Sheet 2 Filed Sept. 29, 1965 March 12, 1968 H. E. STINE, JR

TOOL FOR MAKING ELECTRICAL CONNECTIONS 4 Sheets-Sheet 5 Filed Sept. 29, 1965 March 12, 1968 H. E. STINE, JR

TOOL FOR MAKING ELECTRICAL CONNECTIONS 4 Sheets-Sheet 4 Filed Sept. 29, 1965 United States Patent 3,372,454 TOOL FOR MAKING ELECTRICAL CONNEQTIONS Howard Elroy Stine, Jr., Harrisburg, Pa, assignor to AMP Incorporated, Harrisburg, Pa. Filed Sept. 2@, 1965, Ser. No, 491,357

3 Claims. (Cl. 29-203) ABSTRACT OF THE DISCLOSURE Tool for making clip-type electrical connections comprises reciprocable clip pusher and piston rod. Piston rod is coupled to clip pusher by overload release coupling and by disengageable rigid coupling. Overload release coupling comprises parallel arms mounted on coupling block on end of piston rod; arms are resiliently maintained in engagement with the yoke on the end of the clip pusher. Disengageable rigid coupling comprises detent lever on coupling block having ends which are disposed in recesses in the yoke. During movement of the piston rod, this detent arm is lowered thereby to break the disengageable rigid coupling. Overload release coupling is broken when clip pusher pushes clip against previously applied clip on the terminal post.

This invention relates to apparatus for making cliptype electrical connections.

Clip-type electrical connections are made by moving a terminal clip over a mandrel, past the wire having its end located in an opening in the mandrel, and onto a terminal post. The clip, during its movement over the mandrel, moves against the wire and forms a bight in the wire and thereafter drags the end portion of the Wire over the surface of the mandrel and onto the post. Such clip-type connections are commonly made with a hand tool or a program-controlled applicator as is now commonly known to the art.

It has been found that for best results in making cliptype electrical connections with a hand tool, the tool should be provided with a split-cycle mechanism as disclosed in US. Patent 3,186,075. It has also been found that with tools of the type in which the clip pusher is actuated by a reciprocable piston rod or the like, the tool should be provided with a means for disengaging the actuator from the clip pusher after the clip has been moved a predetermined distance onto the post. A tool having one suitable means for disengaging the actuator from the clip pusher is shown in US. Patent 3,186,072. The reasons for the need of these two features in clip connection tools will be explained in detail as this description proceeds.

An object of the present invention is to provide an improved tool for making clip-type electrical connections. A further object is to provide an improved arrangement of a split-cycle mechanism in combination with a means for disengaging the piston rod from the clip pusher when the clip is moved against a previously applied clip on a terminal post.

These and other objects of the invention are achieved in a preferred embodiment comprising a reciprocable piston rod and a clip pusher for pushing the terminal clip onto the post. The piston rod extends parallel to, and beside, the clip pusher and the clip pusher is provided with a yoke member having sidewalls which straddle a coupling block mounted on the end of the piston rod. This coupling block is coupled to the sidewalls of the yoke by means of an overload release coupling and disengageable rigid coupling, the overload release coupling comprising a pair of parallel arms mounted on a common pivotal axis and having detent means on their ends which engages the sidewalls of the yoke. This overload release coupling is broken when the clip pusher encounters a resistance sufiicient to disengage the detent means. The

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coupling block is also connected to the yoke on the clip pusher by means of a pivoted arm which is normally disposed in a notch means in the yoke sidewalls but which can be carnmed from the notch means during movement of the clip pusher. The preferred embodiment of the in-' vention is also provided with a split cycle mechanism located immediately below the coupling block and which is engaged by a pin extending from the coupling block. A distinct advantage of the invention is that these three features, the two couplings between the piston rod and the clip pusher and the split-cycle mechanism, are compactly and effectively arranged in the tool in a manner such that they occupy a minimum of space but they are, at the same time, readily accessible for servicing or repair.

In the drawing:

FIGURE 1 is a side view, partly in section, of a preferred form of hand tool in accordance with the invention;

FIGURE 2 is an exploded perspective view of the clip pusher, the coupling block, and the split-cycle mechanism;

FIGURE 3 is a transverse sectional view of the tool of FIGURE 1 showing the positions of the parts at the beginning of the operating cycle;

FIGURE 4 is a fragmental view similar to FIGURE 3 but showing the positions of the parts after the overload release coupling of the piston rod and the clip pusher has been broken;

FIGURE 5 is a view taken along the lines 55 of FIGURE 3;

FIGURE 6 is a view taken along the lines 66 of FIGURE 2 and showing the stop means for controlling the movement for feeding of the strip of clips;

FIGURE 7 is a plan view of the split-cycle mechanism showing the positions of the parts at the beginning of the cycle;

FIGURE 7A is a view similar ot FIGURE 7 but showing the positions of the parts at an intermediate stage of the operating cycle;

FIGURE 8 is a sectional view of FIGURE 7 but showing the positions of the parts at the end of the operating cycle; and

FIGURE 9 is a perspective view of a terminal post having several wires connected thereto by clip-type electrical connections.

Referring first to FIGURE 9, a typical clip-type electrical connection 2 comprises a terminal clip 4 mounted on a post 6. The sidewalls 8 of the clip extend partially around the post and the stripped end 12 of the wire is confined between the web 10 of the clip and a surface of the post with the insulated portion 14 of the wire emerging from confined relationship through a strain relief .16 formed at the end of the web. Several clip-type electrical connections can be made on a single terminal post, as shown in FIGURE 9, and it is desirable to control the movement of the clip in a manner such that it is not moved against a previously applied clip since jamming of the clips against each other might result in damage to the clip with a resulting inferior electrical connection.

A preferred form of hand tool in accordance with the invention has a depending handle 20 and a pneumatic cylinder 22 and piston rod 24. The cylinder head has a pair of integral bosses 26, 28 which are utilized to support the frame structure (FIGURE 2) of the tool mechanism. This frame structure comprises a forwardly extending frame member 30, a downwardly and obliquely extending frame portion 32, and a rearwardly extending plate 34 which is supported on the frame member 32. This frame structure and the mechanisms associated therewith are supported between a pair of side plates 36, 38 (FIGURE 3) the latter plate having an upper flange 40 which covers the upper portions of the tool. It will be understood that the frame members and the cover plates will be retained in position by suitable fasteners as indicated.

The terminal clips in strip form are supplied from a reel 42 mounted on a bracket 44 above the cylinder 22 and are fed by means of a clip pusher 46 over the upper surface of the frame member 30. The clip pusher is of channel-shaped cross-section and straddles the strip of clips. At its forward end, this clip pusher is provided with inwardly directed fingers 50 which lodge between the leading clip of the strip and the next adjacent clip and push the leading clip over the mandrel (described below) and onto the post. The clip pusher may be provided with a channel-shaped liner 48 by means of which its internal dimensions are made to conform to the external dimensions of the strip of clips. The frame member 30 is provided withan inwardly extending recess 52 at its forward end Within which a mandrel block 54 is mounted. A mandrel on the upper side of this block comprises a rib 56 and a head portion 58, the rib being in alignment with the path of movement of the clip pusher so that the strip is fed over the head portion of the mandrel. An opening 60 is provided in the mandrel intermediate its ends for the reception of the end portion of the wire which is to be connected to the post. A relatively thin plate 62 is mounted in a slot 64 in the frame member 30 in alignment with the mandrel and the upwardly projecting portion of this plate functions as a guide rib for the strip of clips. An ear 66 is struck from the plate at its forward end and extends obliquely with reference to the path of feed of the strip of clips to function as a stop member for preventing rearward movement of the strip.

In addition to the stop 66, an additional displaceable stop 68 is provided on the path of feed of the strip to prevent feeding of more than one clip at a time. This displaceable stop is mounted in the recess 52 and is connected by means of a transversely extending pin 70 to a pair of levers 72 mounted in slots 74 on each side of the slot 64. The levers 72 are pivotally mounted at their right-hand ends as viewed in FIGURE 6 on a pin 76 and have upwardly extending ears 78 intermediate their ends. A bar 80 extends between these ears and a recess 82 is provided in the frame member 30 beneath this bar to permit downward movement of the bar and the ears when the clip pusher moves over the ears as will be apparent from FIGURE 6. This arrangement for controlling the movement of the strip of clips is in many respects similar to the arrangement shown and claimed in copending application Ser. No. 419,175, now Patent No. 3,220,099, granted Nov. 30, 1965.

The clip pusher is provided with laterally extending flanges 84 at its rearward end (FIGURE 3) which are welded or otherwise secured to the top of a yoke member 86 having depending sidewalls 88. These sidewalls straddie the frame member 30 and also straddle an L-shaped coupling block 90 mounted on the end of the piston rod 24. The forwardly extending arm 92 of this coupling block is provided with an elongated slot 94 in which a pin 96 is disposed. The ends of this pin have reduced diameter sections which are received in notches 98 in the sidewalls 88 of the yoke. The purpose of this pin is merely to prevent outward flexure of the sidewalls and it does not function as a lost-motion coupling between the block and the yoke.

An overload release coupling between the coupling block 90 and the yoke 88 is provided in the form of a pair of parallel arms 100 mounted on the forwardly extending portion 92 of the coupling block on a common pivotal axis 102. At their rearward ends, these arms are provided with notches in which are mounted rollers 104 on pins 105 extending into the arms as shown best in FIGURE 3. The pins 105 also extend through oversized openings 108 in a plate 106 thereby to permit limited arcuate movement of the two arms with respect to their pivotal axis 102. The arms are biased apart by means of a spring 110 which bears against their opposed surface, a set screw 112 being provided in one of the arms to permit adjustment of the degree of compression of the spring, see FIGURE 5.

The rollers 104 are normally extended partially into openings 114 in the sidewalls 88 of the yoke 86 and the rollers and openings, therefore, constitute a detent-type coupling between the coupling block and the sidewalls which can be broken when the resistance encountered by the clip pusher exceeds a predetermined level.

A disengageable rigid coupling between the coupling block and the clip pusher is provided in the form of a lever 116 pivotally mounted on a pin 120 in a notch 118 in the upper end of the coupling block 90. The forward end of this lever has a boss 124 within which a pin 126 is contained. The projecting ends of this pin are normally lodged in the seat portions 128 of notches in the sidewalls 88 of the yoke. These notches are so contoured that the pins will normally bear against the depending surfaces 130 thereby constituting a rigid coupling between the coupling block and the yoke. The lever 116 is normally biased upwardly by a spring 122 to maintain this coupling in engagement although the coupling can be broken if the lever is swung downwardly against the compression of the spring 122. The lever is, during movement of the coupling block, swung downwardly by an obliquely extending camming surface 134 on the underside of the frame member 130.

As explained in detail in US. Patent 3,186,072, the rigid coupling between the coupling block 90 and the clip pusher is required while the terminal clip is being pushed over the mandrel and particularly while the wire is being dragged from the opening 60 in the mandrel since substantial resistance is encountered during this portion of the operating cycle. After this portion of the cycle has been completed, this disengageable rigid coupling is broken by the camming means 134 and for the remaining portion of the cycle, the coupling block is coupled to the yoke member by the overload release coupling only. The overload release coupling is broken when the yoke member moves against a stop screw located in one of the openings 136 in the side plate 36. This arrangement permits the use of a fixed stroke piston cylinder on the tool but prevents the clip pusher from jamming a clip against a previously applied clip with the resulting possibility of damage to the electrical connection produced.

The split-cycle mechanism 138 is a desirable feature in tools of the instant type for the reason that it permits the operator to hold the tool in any convenient orientation while he is inserting the wire into the opening 60 in the mandrel and effecting the initial movement by the clip pusher of the clip over the mandrel head. After he has brought about these operations, he can then position the tool against the end of the post and he is free to concentrate on the critical operation of properly aligning the tool with the post. It should be added that a split-cycle mechanism of the type described below is intended for usage with a piston-cylinder in which the piston rod will return to its starting position as soon as finger pressure is released from the trigger which controls the valve. A conventional double-acting pneumatic piston-cylinder or a single-acting piston-cylinder with a return spring in the cylinder could thus be used with the split-cycle mechanism 138.

This split-cycle mechanism is actuated by a pin 140 which extends downwardly from the underside of the coupling block 90. The mechanism comprises a flat platelike lever 142 having an integral pin 143 on its underside which extends into an elongated slot 144 in the plate 34. The right-hand side of this lever bears against a stop pin 146 in the plate 34 and the lever is biased in a clockwise direction as viewed in FIGURE 7 by a spring 148 mounted on a pin 150. The left-hand side of this lever is provided with opposed pockets 152, 154 adjacent to its ends which conform to the radius of the pin 140. At the beginning of the operating cycle, this pin is seated in the pocket 152, as shown in FIGURE 7.

An additional lever 156 is mounted on the pin 150 and extends transversely across the plate 34 and over the lever 142. Lever 156 is biased in a counterclockwise direction to the position in FIGURE 7 by means of a torsion spring 158 having one of its arms mounted in the plate 34 and having its other arm mounted in the lever.

This lever is also provided with a pocket or cut-out 160 on its left-hand side as viewed in FIGURE 7 and an arcuate guide 162 partially closes this pocket. Guide 162 is pivotally mounted on a pin 164 in the lever and which extends into an arcuate slot 166 in the plate 34. A stop 168 is struck up from the lever adjacent to its end to prevent arcuate movement of the guide beyond the stop.

The operation of this split-cycle mechanism is as follows: The parts will normally be in the positions of FIG- URE 7 at the beginning of the operating cycle. The operator first inserts the wire in the mandrel opening 60 and pulls the trigger to cause leftward movement of the piston rod and the coupling block 90. The coupling block moves towards the forward end of the tool and the pin 140, during such movement, swings the lever 156 through a slight clockwise arc until it moves to the pocket 154 of the lever 142. The pin 140 drags the lever upwardly, as viewed in FIGURE 7, until the pin 143 moves to the upper end of the notch 144 as shown in FIGURE 7A. When the pin 143 moves to the end of this notch, further upward movement of the coupling block is arrested. The operator then releases finger pressure on the trigger and the coupling block is retracted until the pin 140 moves against the end of the notch 160 in the lever 156. When this happens, the lever 142 is swung through a slight clockwise are under the influence of the spring 148 and is thus moved out of the way of the pin 140. The operator then positions the tool against the terminal post and again depresses the trigger. The pin 140 thereafter moves upwardly past the guide 162 which will be swung against the stop 168. The pin 140 will then swing the lever 156 through a further clockwise arc until it reaches the position of FIG- URE 8 at the end of the stroke. During return movement of the pin 140 from the position of FIGURE 8 to the position of FIGURE 7, the pin 140 will swing the guide 162 to its initial position and will thereafter move into the pocket 152 and return the lever 142 to its starting position. The guide 162 functions to prevent the pin 140 from moving into the pocket 161 of the notch 160 during rearward movement of the coupling block.

The tool in accordance with the invention achieves all of the features of the tools shown in U.S. Patents 3,186,072 and 3,186,075 in a compact and easily serviced arrangement with the two couplings between the piston rod and the clip pusher disposed symmetrically beneath the clip pusher. All of the coupling mechanisms and split mechanism are, moreover, conveniently arranged to permit repairs or servicing when necessary.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

I claim:

1. In an apparatus for making clip-type electrical connections between a conductor and a terminal post comprising a reciprocable actuator and a reciprocable clip pusher, said apparatus having an overload release coupling and a disengageable rigid coupling between said actuator and said clip pusher, the improvement comprising, a coupling block on said actuator, a yoke on said clip pusher in straddling relationship to said coupling block, said overload release coupling comprising a pair of substantially parallel arms pivotally mounted on said coupling block, said arms being normally disposed between the sidewalls of said yoke, detent means effective between said arms and said yoke, said detent ments being disengageable to permit independent movement of said coupling block and said actuator when said clip pusher encounters a resistance of predetermined magnitude, said disengageable rigid coupling comprising notches in said yoke and a spring based lever on said coupling block, said lever having portions thereof normally disposed in said notches, and camming means engageable with said arm to disengage said rigid coupling during movement of said clip pusher.

2. In a tool for making clip-type electrical connections and comprising a reciprocable clip pusher and a reciprocable actuator for said clip pusher, the improvement comprising, an improved coupling assembly between said clip pusher and said actuator, said coupling assembly comprising, a yoke on said clip pusher and a coupling block on said actuator, said yoke having a pair of sidewalls in straddling relationship to said coupling block, a pair of parallel arms on said coupling block, and normally disposed between said sidewalls, spring means biasing said arms apart and against said sidewalls, overload release interengaging means acting between said sidewalls and said arms, said overload release means constituting an overload release coupling between said actuator and said clip pusher, a pivoted lever on said coupling block, said lever being normally engaged with said yoke, and camming means for disengaging said lever from said yoke during movement of said actuator.

3. In an apparatus for making clip-type electrical connections and comprising a reciprocable thrust applying member and a clip pusher, said thrust appling member having an overload release coupling and having a disengageable rigid coupling with said clip pusher, said couplings being in parallel with each other, said apparatus including means for disengaging said rigid coupling during the working stroke of said thrust applying member, the improvement to said apparatus comprising, an L- shaped coupling block on said thrust applying member and a yoke member on said clip pusher, said yoke member having parallel sidewalls in straddling relationship to said coupling block, a pair of parallel arms on said coupling block, said arms being pivotally mounted at one end on a common axis extending medially between said sidewalls and normally of the path of reciprocation of said clip pusher, resilient means between said arms biasing said arms apart and towards said sidewalls, and detent means on said arms in engagement with said sidewalls whereby, said overload release coupling is broken when said clip pusher encounters a resistance of predetermined magnitude sufficient to overcome said resilient means.

References Cited UNITED STATES PATENTS 3,186,072 6/1965 Cobaugh 29-203 3,186,075 6/1965 Vickery 29203 3,220,099 11/1965 Long 29-203 THOMAS H. EAGER, Primary Examiner. 

